As Decoder wrote earlier today, Mitt Romney is attacking Rick Perry for his comments on Social Security at the last debate (where he called it, among other things, a “monstrous lie.”) Ex-presidential candidate and former Minnesota Gov. Tim Pawlenty also brought up Social Security in his endorsement of Romney this morning. Michele Bachmann, who followed up her win at the Iowa straw poll by fading back to single-digit national polling, is also reportedly preparing the long knives on Social Security to try to get some mojo back.

In short, Rick Perry has Michele Bachmann’s mop on his head a target on his chest tonight. Still, the Texas governor might take some comfort from the way this debate has played out in GOP primaries past: The back-and-forth between Perry and Romney has similarities to that between then-presidential hopefuls John McCain (playing Romney) and George W. Bush (playing Perry) in South Carolina in 2000. Watch for Social Security sparks to fly early and often tonight, in a debate that is being held in Florida, with its large pensioner population, but is also sponsored by the stridently anti-government tea party.

Mitt Romney busted out a 160-page jobs plan, which followed Jon Huntsman’s 16-page proposal, and which President Obama jumped on top of with a $475 billion plan of his own. While more than half of Obama’s proposals (measured in dollars) are straight out of the GOP playbook - including cutting payroll taxes for both employers and employees - it will be key to see what pieces of the proposal Republican candidates focus their fire on tonight, and whether any of the as-yet uncommitted announce their own jobs plans.

3. What role will the second-tier candidates play?

"The obvious temptation is to let the frontrunners get most of the air. But I don’t want to do that: And so it’s hard. You want to make sure that you can give, at least as best as you can, roughly equal time to all of these eight candidates.

"Decoder thinks even “roughly” equal time for candidates will be highly unlikely given that everybody is going to be trying to score points off of Perry (and to a lesser extent Romney) which will give those two many chances to respond and suck up further air time. Still, the role all the other candidates play - from Bachmann, who has a devoted tea party following; to Rick Santorum, who isn’t afraid to throw his weight around on social issues; to Ron Paul, who mixed it up with Perry at the last debate - is a definite wild card.